Related papers: Tuning the graphene work function by electric fiel…
We compare the three most commonly used scanning probe techniques to obtain a reliable value of the work function in graphene domains of different thickness. The surface potential (SP) of graphene is directly measured in Hall bar geometry…
Scanning Kelvin probe microscopy (SKPM) is a powerful technique for macroscopic imaging of the electrostatic potential above a surface. Though most often used to image work-function variations of conductive surfaces, it can also be used to…
Graphene, a two-dimensional (2D) material with unique electronic properties, appears to be an ideal object for the application of surface-science methods. Among them, a family of scanning probe microscopy methods (STM, AFM, KPFM) and the…
Electron beam exposure is a commonly used tool for fabricating and imaging graphene-based devices. Here we present a study of the effects of electron-beam irradiation on the electronic transport properties of graphene and the operation of…
We report a theoretical study of the many-body effects of electron-electron interaction on the ground-state and spectral properties of double-layer graphene. Using a projector-based renormalization method we show that if a finite voltage…
Controlled modification of graphene properties is essential for its proposed electronic applications. Here we describe a possibility of tuning electrical properties of graphene via electron beam irradiation. We show that by controlling the…
We study how the Fermi energy of a graphene monolayer separated from a conducting substrate by a dielectric spacer depends on the properties of the substrate and on an applied voltage. An analytical model is developed that describes the…
We use a combination of charge writing and scanning gate microscopy to map and modify the local charge neutrality point of graphene field-effect devices. We give a demonstration of the technique by writing remote charge in a thin dielectric…
Making devices with graphene necessarily involves making contacts with metals. We use density functional theory to study how graphene is doped by adsorption on metal substrates and find that weak bonding on Al, Ag, Cu, Au and Pt, while…
The orbital magnetism in spatially varying magnetic fields is studied in monolayer graphene within the effective mass approximation. We find that, unlike the conventional two-dimensional electron system, graphene with small Fermi wave…
In 2D field effect transistors the gate electrostatically dopes the 2D semiconductor (2DSC) channel, tuning the Fermi level. In principle, Kelvin probe force microscopy (KPFM) can detect the Fermi level, and its dependence on gate bias as…
Specific contact resistivity measurements have conventionally been heavy in both fabrication and simulation/calculation in order to account for complicated geometries and other effects such as parasitic resistance. We propose a simpler…
The electron-electron interactions effects on the shape of the Fermi surface of doped graphene are investigated. The actual discrete nature of the lattice is fully taken into account. A $\pi$-band tight-binding model, with nearest-neighbor…
The scanning Kelvin probe is a tool that allows for the contactless evaluation of contact potential differences in a range of materials, permitting the indirect determination of surface properties such as work function or Fermi levels. In…
The rapid technological progress in the 21st century demands new multi-functional materials applicable to a wide variety of industries. Two-dimensional (2D) materials are predicted to have a revolutionary impact on the cost, size, weight,…
The effect of external static charging of graphene and its flakes are investigated by using first-principles calculations. While the Fermi level of negatively charged graphene rises and then is quickly pinned by the parabolic, nearly free…
High-quality spatially-resolved measurements of electric fields are critical to understanding charge injection, charge transport, and charge trapping in semiconducting materials. Here, we report a variation of frequency-modulated Kelvin…
It is demonstrated that the electric dipole layer due to the overlapping of electron wavefunctions at metal/graphene contact results in negative Fermi-level pinning effect on the region of GaAs surface with low interface-trap density in…
We study a graphene Hall probe located on top of a magnetic surface as a detector of skyrmions, using as working principle the anomalous Hall effect produced by the exchange interaction of the graphene electrons with the non-coplanar…
The electrical characterisation of graphene, either in plane sheets or in properly geometrised form can be approached using non-contact methods already employed for thin film materials. The extraordinary thinness (and, correspondingly, the…